Cotter key



Feb. 5, 1935. J. w. PETERSON COTTER KEY Original Filed Jan. 29, 1952Reissued Feb. 5, 1935 UNITED" STATES PATENT OFFICE 7 19,4522 5 1 flv w iJohn W. Peterson, Cairo, Ill. Original Pia-1,903,129, dated Marches,"193:5, j

Serial No. 589,576, January 29,1932; Application for reissue June 25,1934, Serial N 732,379 t -14 Claims. (CI. -85) i This invention relatesto improvements in cotter keys or cotter pins of the general type havingtwo legs for insertion through a bore or opening of a bolt, nut, shaft,or other machine element, for the purpose of retaining parts inassembled relationship.

A general object of the invention is the'provision of such a cotter keywhich-will perform :its intended function effectively, and which can beinserted and securely fastened in place, and which requires, in itsuse,'much less time and labor for the assembling and securing of it'inplace than is involved in the use of cotter keys heretofore generallyemployed. I

Another object is the provision of a cotter key of the sort describedwhich may be easily and freely inserted through an opening ofappropriate size, and which automatically locks itself againstwithdrawal, yet may 'be withdrawn with facility upon propermanipulation.

Another object is the provision of a cotter key which, by virtue ofitsautomatic locking characteristic, is particularly qualified for assemblyin locations affording limited or-restricted working space.

Yet another object is the provision of a cotter key possessing theattributes "indicated above, which may be manufactured economicallyand-in quantities with uniformity in dimensions and design, and whichalso may be made in a great variety of sizes.

Other and further objects will be pointed out or indicated hereinafter,or willbe apparent to one skilled in the art upon an'understanding ofthe invention or its employment in use.

For the purpose of aiding in the explanation of the invention, I show inthe accompanying drawing forming a part of this specification, variousforms and features o'f cotter' keys injwhicl i. the invention isembodied, but it is to be understood that these and the followingdescriptionare pre; sented merely by way of example and illustration,and are not to be accorded any interpretation calculated to limit theappended claims short of the true andmost comprehensive scope of theinvention in the art, as I am. aware that it may be embodied in manyother specific forms, and that the features herein illustrated anddescribed may be modifiedin various particulars without departing fromthe spirit of the invention or the intended scope of the claims.

In said drawing,

Fig. 1 is an illustration of one form of my improved cotter key with itsportions iii-positions whichthey assume under normal or unrestrainedcondition of the metal;

5 Fig. 2 .is .an illustration. of the same form of key with partsretained in a tensioned condition and in positions in which theyareretained pre liminary to and incident to insertion through theintendedkey seat or aperture;

f Fig. 3 isan illustration of the same form of key in its seated andsecured relationship with a bolt, shaft, or the like; 'f

Fig. 4 is an illustration of a modified form of key embodying theinvention, with the parts in normal or untensioned positions;

' Fig.5, an illustration of .a second modified form of key. embodyingthe invention, with its parts'in thejnorm'al or untensioned position;

Fig. 6 is a detail, in the nature of a side elevation of the left endportionof Fig. 2, and serves to illustrate one. form of latching meansand the relationship of parts in the latched condition;

-Fig. 7 illustrates, anotherform oflatching or holding element,thefigure-being a detail of the end of a pin leg; 1

Fig.8 is anothervi'ew of the same, looking at the bottom of Fig. '7;

Fig. 9 is a detail similar to Fig. 6, showing a second modified form oflatching or holding members; Q s r Fig. 10 .is inv thenature of a, leftend view of Fig. I 9, but with the latching or holding membersseparated; and f I Fig. 11 is" an illustration of afurther modifiedformof the bight or loop of the key.

"Described generally, the invention contemplates 3. cotter key or pinhaving two arms or legs connectedby a'bight, head or loop, and of suchnature that when unrestrained, the legs tend {to assume'a' sprea'd'orseparated relation ship; considerably exceeding in their span thediameter of theseat or aperture in which the keyjis to'be inserted andsecured. The legs of the jkey, or their connecting bight or head, orboth, are'of a resilient or; elastic character, permitting the legs tobe pressed together into close association with each other, and at theend of one or both of the legs is provided a latching or holdingelement, whereby the legs may be retained in thatrelationship againstthe tension which'tendstomove them to the separated or spread position.This latching or holding arrangement is such that the ends of the legsmay be very easily and quickly freed from this retention,'to allow themto spring apart under the inherent elasticity or resiliency of thedevice. Atthe end of one or both of the legs is provided a stop orabutment member which projects outwardly from the leg in a position toengage against a surface of the element in which the key is seated, forthe purpose of preventing withdrawal of the key from the seat. The heador bight of the key serves in similar fashion to prevent withdrawal ofthe key from the seat in the opposite diredion. I

A more detailed understanding of theinvention may be had from theillustrative embodiments shown in the drawing. In Fig. 1 is il-'lustrated a key formed of wire, which may he 01' any appropriatecross-sectional form, the key being shaped with the legs 10 and 11connected by a loop or bight 12, the wire being of a tempered orresilient character such that the legs tend strongly to assume thespread or relative positions approximately as shown. At the free end ofthe leg 10 the wire is bent reversely back along theouter side of thelegto form an abutment or stop'member 14, the tip. of which-is bentupwardly to a position somewhat above the leg wire 10, to form alatching or retaining member 15; The parts are illustrated on a somewhatlarger scale in 6. The wire at the free end of the leg llis bentreversely back along the outer side of the leg wire, for a lengthsomewhat less than that. of the reversed portion 14, and this portion'16 is adapted to constitute an abutmentor stop member. The provisionoithis member 16, while desirable, isoptional, but not essential. V

The key may be shaped from wire having the proper resiliency, or thewire may be shapedwhile in a mild or annealed condition, to form the keyabove described, and then tempered, to give it the desired set.and'spring quality.

The device having. the proper'spring quality,

the wire is placed under tension by pressing the legs together andcrossing or partly crossing one over the other, as in the positionsillustrated in Fig. 2, and the key is latched intl'u's tensionedconditionv by engaging the leg 11' against the outer side of thelatching or retaining member 15, the parts being held in thisrelationship by the spring tension of the wire. The key is now incondition suitable for insertion through the intended key seat oraperture. This contracting or tensioning and latching .oi theikey may bedone as a part of its manufacture, in which-case, the key is marketed inthat condition.

' In this contracted or latched condition, the legs are close together,and may be quickly and easily inserted through a suitable key seat oraperture to a distance suchthat 'thelatched ends of the legs-protrude.Thereupon, the key may be quickly and easily set or secured simply bydisengaging theleg 11 from the latching member 15, which may beaccomplished readily by the insertion of a prying implement between theends of the legs. Immediately the leg 11 is disengaged from the latchingmember, the legs spring apart under the tension of the material, to theextent permitted by the key seat or aperture, thus assuming a positionas illustrated for example in Fig. 3. The elastic tension of thematerial holds the legs in contact with the opposite wall portions ofthe key seat, and the key is retained against withdrawal byabutment ofthe abutment or stop member or members against the. adjacent side of thetransfixed member. The continuous spring pressure of the key legs on thewall portions of the seat holds the key against rattling. 'I'hekey maythus be inserted in close proximity to washers or other elements mountedon the transfixed member, or through collars, castellated nuts, or othermembers provided with suitable apertures or keyways in register with thekey seat. 1

The bight, loop, or head of the key may be made in any of a greatvariety of forms, certain variations in this particular beingillustrated in Figs. 4, 5 and 11. t ,7

The latching member and stop members may be formed in various fashions.For example, in 4, 5, 7 and 8 is illustrated an arrangement wherein thelatching member 15 is provided by 9 9 the reversely bent end of the legwire under the latter and turning the tip up at the inside of thelegwire. In Figs. 9 and 10 is illustrated another fashion in whichcooperating latching members may be formed at the ends of the legwires,by bending the ends of the wires reversely alongside the leg wires andthen swag- :mg the bent portion to iormcomplementary shouiders oroffsets 15' adapted to engage each other to hold thele'gs under tension.In Fig. 10 the arrows indicate the direction of the spring tendency ofthe leg members. in the others, the reversely bent ends of the leg wiresform stop members, as indicated at 14'.

The temper set of the material may be such as to cause the-legato spreador separate in crossed relationship, as'ilhistratedfor example in Fig.4,

which has to be spread at the ends; and it is to i be observed'likewisethat the proper setting of the key is efiected with certainty. Whilespring keys have beenheretofore proposed for use, it has been diflicultto accomplish their insertion; due-to the fact that the legs had to beheld together by pliers or the like in order to efiect theirintroduction into the aperture.- This disadvantage is entirelyeliminated by my present invention, as the legs are held together by thelatching arrangement.

Hence the pinmay be handled entirely by the head J or bight. Thisfacility of insertion and locking isofparticular advantage wheretheworking space is restricted or the key seat is close to washers,collars, or the like. The key may be as readily removed, by latchingthe'ends of the legs as above describedso it may. be withdrawn by thehead, or. asis the usualpractice, by cutting off the head, or ends of.thelegs. and then withdrawing it. The leg members may be serrated,knurled or sinuouslyformed for the purpose of increasing their bite orholding efi ect upon the wall portions of thexkeyseat. 7 v

What I claim is:

1. 1i cotter key comprising a pair of legs conjoined bya head andtending normally to assume a spread relationship, said key formed topermit the end portions of the legs to be overlapped one upon the other,a latching'member carried adjacent the end of one leg for latchingengagement with the other leg to hold the legs close together andunder'elastic tension in positions such that the over-all width of thekey across the ends of the legs is less than that of the head, and astop member projecting outwardly from one of the legs adjacent the freeend thereof.

In this form, as :3

Iii)

2. A cotter key comprising a pair of legs conjoined by a head andtending normally to assume a spread relationship, said key formed topermit the end portions of the legs to be overlapped one upon the other,latching members carried adjacent the ends of the legs and adapted forinterengagement when end portions of the legs are in overlapped positionto hold the legs close together and under elastic tension in positionswherein the maximum distance across the legs is less than the maximumwidth of the head, and a stop member projecting outwardly from one ofthe legs adjacent the free end thereof.

3. A cotter key comprising a pair oi legs conjoined by a head andtending normally to assume a spread relationship, said key formed topermit the end portions of the legs to be overlapped one upon the other,a latching member carried adjacent the end of one leg for latchingengagement with the other leg to hold the legs under elastic tension inpositions relatively close together, and stop members carried on thelegs adjacent the ends thereof and projecting outwardly therefrom in thedirections in which the legs tend to separate.

4. A cotter key as specified in claim 2 which, inclusive of the latchingmembers, is formed throughout of a single length of spring wire.

5. A cotter key as specified in claim 1 and wherein the latching memberprojects from the leg in one direction and the stop member projects inanother direction.

6. A cotter key as specified in claim 2 and wherein the latching membersare formed as ppositely directed projections on the leg portions.

'7. A cotter key comprising a pair of legs conjoined by a head andtending normally to assume a spread relationship, said key formed topermit the end portions of the legs to be overlapped one upon the other,a latching member carried adjacent the end of one leg for latchingengagement with the other leg to hold the legs under elastic tension inpositions relatively close together, and stop members projectingoutwardly in opposite directions adjacent the free ends of the legs, thestop member on one leg being spaced a less distance from the head thanthe stop member on the other leg.

8. A cotter key formed of spring wire with two leg portions tending toassume a spread and separated relationship, the wire at one end of a legmember being bent reversely to a position along the outer side of saidleg member and part of the reversely bent portion being off-set to forma catch engageable by the other leg member, whereby the leg members maybe latched in proximate relationship and held under elastic tension.

9. A cotter key having two legs connected by a head and elasticallyconstrained toward spread relationship, a latching member carried by one01' the legs and adapted for latching cooperation with the other leg toretain the legs under elastic tension with their ends relatively closetogether, and a stop member carried adjacent the end of one leg andprojecting outwardly therefrom on the side opposite the other leg, saidlatching and stop members being insertable through the key-way with thelegs when the latter are latched together.

10. A cotter key having two connected legs elastically constrainedtoward a spread position, one of the legs being formed adjacent its freeend with a stop member extending outwardly in the direction away fromthe other leg and one of the legs being formed adjacent its free endwith a latching member for latching engagement with an end portion ofthe other leg.

11. A cotter key having two leg portions elastically constrained towardspread relationship and movable to a crossed relationship, and alatching member carried on one of the leg portions for latching the legportions in crossed relationship under elastic tension with their endsclose together.

12. A cotter key having two leg portions connected by a head portion andtending normally to assume a separated relationship at their free ends,said leg portions having stop members projecting therefrom adjacenttheir free ends and having also interengageable parts whereby they maybe hooked together under elastic tension to hold the outer sides oftheir free ends and stop members closer together than the outer sides ofthe head, for insertion through the key seat.

13. A cotter key having two leg portions connected by a head portion andtending normally to assume a separated relationship at their free endsand adapted to have their free ends moved into overlapping relationshipunder elastic tension, said leg portions having stop members projectingtherefrom adjacent their free ends and having also interengageable partswhereby they may be hooked together under elastic tension to hold theirfree ends and stop members sufi'iciently close together to permit theirinsertion through a key seat which will not admit the head.

14. A cotter key comprising a pair of legs conjoined by a head andtending normally to assume a spread relationship, one of the legportions having a part projecting laterally in a direction away from theother leg to form a stop member adapted for latching engagement with apart of the other leg to hold the legs under elastic tension inpositions wherein the maximum distance across the legs and stop memberis less than the maximum width of the head.

J. W. PETERSON.

